See the most controversial, heated and tragic moments in Olympic history.

Photo: NBC

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The most controversial, heated and tragic moments in Olympic history

The most controversial, heated and tragic moments in Olympic history

Photo: Transitionslyde

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Nazi Germany Olympics

Two years before the Nazis came to power in Germany, Berlin was selected to host the 1936 Summer Olympics. As the Olympics approached, many countries, including the U.S., considered boycotting the Olympics due to Nazi ideas of racial superiority.

Jesse Owens (1913 - 1980) of the USA (right) crosses the finishing line to win the 100 metres at the 1936 Olympics in Berlin. He won three other gold medals, in the 200 metres, 4 X 100 metres relay and long jump.

Both the 1940 and 1944 Summer Olympics were canceled due to the outbreak out World War II. The 1940 Summer Olympics were meant to take place in Tokyo, Japan. They were later moved to Finland, which was invaded by the Soviet Union.

During the 1956 Summer Olympics in Melbourne, Australia, Hungarian and Soviet players played a violent match of water polo. The Soviet Union had invaded Hungary during the time of the Olympics in order to suppress a revolution. The match became known as the "Blood in the Water match."

Blood streams from the cut eye of Ervin Zador- injured during a brawl with Russian water polo players during closing minutes of the Soviet-Hungary match. The match ended in chaos with the crowd booing the Russians. Throughout the match, which Hungary won 4-0, fists, elbows, knees and feet were used whenever the players came in contact.

Blood streams from the cut eye of Ervin Zador- injured during a brawl with Russian water polo players during closing minutes of the Soviet-Hungary match. The match ended in chaos with the crowd booing the

In solidarity with the Civil Rights Movement in the U.S., Tommie Smith and John Carlos, gold and bronze medalists in the 200-meter run at the 1968 Olympic Games, made a Black Power salute. The two players were eventually suspended from the Olympic Village.

Suspended U.S. Olympic star John Carlos and his wife are shown as they leave Olympic Village after the U.S. Olympic Committee's decision to order Carlos and fellow sprinter Tommie Smith out of the country due to the Black Power demonstration that was staged during the Olympic awards ceremony.

During the 1972 Summer Olympics in Munich, West Germany, eight Palestinian terrorist took 11 Israeli athletes hostages, eventually killing them.

Munich massacre

During the 1972 Summer Olympics in Munich, West Germany, eight Palestinian terrorist took 11 Israeli athletes hostages, eventually killing them.

Photo: Co Rentmeester/The LIFE Picture Collection/Getty Images

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Munich massacre

An armed German policeman, dressed as an athlete, stands around the corner from a balcony of a dormitory where members of the Black September terrorist group had earlier captured and were then holding a group of Israeli athletes hostage, Munich, Germany, September 5, 1972.

In response to the Soviet invasion of Afghanistan, the United States boycotted the 1980 Summer Olympics in Moscow.

U.S. Boycott

In response to the Soviet invasion of Afghanistan, the United States boycotted the 1980 Summer Olympics in Moscow.

Photo: Wally McNamee/Corbis Via Getty Images

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Soviet Union Boycott

In retaliation to the U.S. boycott of the 1980 Olympic games held in Moscow, the Soviet Union and 14 other countries boycotted the 1984 Olympics held in Los Angeles.

Soviet Union Boycott

In retaliation to the U.S. boycott of the 1980 Olympic games held in Moscow, the Soviet Union and 14 other countries boycotted the 1984 Olympics held in Los Angeles.

Photo: Pool FRANCOLON/SIMON/Gamma-Rapho Via Getty Images

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Centennial Olympic Park bombing

During the 1996 Summer Olympics in Atlanta, Georgia, a terrorist protesting abortion in the U.S. detonated a pipe bomb killing two persons and injuring 111 others.

Centennial Olympic Park bombing

During the 1996 Summer Olympics in Atlanta, Georgia, a terrorist protesting abortion in the U.S. detonated a pipe bomb killing two persons and injuring 111 others.

Photo: DIMITRI MESSINIS/AFP/Getty Images

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Korean Unification Flag

During the opening ceremonies of the 2000 Summer Olympics in Sydney, Australia, North and South Korean delegations marched together holding the Korean Unification Flag for the first time. The flag displays the Korean peninsula.

In 1964, South Africa was banned from the Olympic Games because of its apartheid laws.

Banning South Africa from the Olympic games

In 1964, South Africa was banned from the Olympic Games because of its apartheid laws.

Photo: Keystone/Getty Images

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Anti-gay laws during Sochi Olympics

Protests surrounded much of the 2014 Winter Olympics in Sochi, Russia after the country banned the promotion of 'non-traditional' sexuality. President Obama responded by sending an openly gay tennis player as part of the U.S. delegation in the game's opening ceremony.